1. Field of the Invention
The present invention relates to an automatic solar heating system for open-air swimming pools with a basin for holding the bathing water.
2. Description of the Prior Art
Open-air swimming pools in only very few regions of the world reach bathing water temperatures which, without additional heating, guarantee real bathing pleasure.
As a rule, agreeable water temperatures can only be achieved with additional heating. However, the additional heating costs for this are considerable. The commonly applied heating method for producing warm water is by way of a gas or oil heater. In addition to the actual installation costs for such a heating system, considerable operation costs are also incurred on account of the expensive fuel in the form of oil or gas. The number of built private or public open-air swimming pools has decreased in the last twenty years.
In order to reduce the energy costs, so-called solar systems have been offered as alternatives. This relates to tubular systems laid out in a serpentine form and pressed into mats through which the bathing water taken from the open-air swimming pool is fed by means of a separate pump, heated by the sun and led back into the open-air swimming pool. The tubular systems are suitably arranged in a position especially exposed to the sun. Therefore, the tubular systems are usually arranged on the roof of a house, preferably an inclined roof and, as a rule, the orientation to the sun is in the south-west position in the northern hemisphere of the earth. The tubular systems can also be mounted in frames. A laying out of the tubular system is generally also possible on the ground surrounding the open-air swimming pool, for example in a garden.
However, such solar systems involve considerable disadvantages. Tubular systems arranged on roofs are only orientated in one direction to the sun and can not be made to follow the bath of the sun. A favourable solar irradiation angle can therefore only be realized in a very limited range of the path of the sun, on account of which a small coefficient of efficiency and thus a poor utilisation of the available solar energy results. Additionally, the daily duration of use of this solar system is greatly reduced on account of the above-described circumstances. Although apparatus for following the path of the sun are known in solar units, the costs of such devices are so high that their future use is initially limited only to solar systems in research.
As the tubular systems are positioned on inclined roofs or frames set up at an angle to achieve a favourable sunshine irradiation angle, the heating performance of the tubular system is reduced on account of cooling through the influences of wind. The solar tubular system additionally requires a separate pump in order to maintain the heating circulation and therefore consumes additional energy. The greater the level difference to be overcome between the water level of the open-air swimming pool, usually located on flat ground, and the tubular system arranged on the roof the higher the energy requirement. Additionally, the hose-like tubular systems mounted on the roof or laid out in the garden present an optically very unaesthetic view so that this version of the solar heating system only finds very low acceptance amongst open-air swimming pool owners.